The air necessary for the combustion process is usually fed to a combustion engine via an air feed. As a rule, this air is conducted into a combustion chamber delimited by a cylinder via an inlet valve. For driving a piston, an air-fuel mixture is ignited in the respective combustion chamber. Because of this, exhaust gas is created, a certain amount of which can enter a crankcase passed the piston. Here, the crankcase encloses at least one crankshaft, which is connected to the respective piston. In order to avoid a positive pressure in the crankcase created through these blow-by gases, the combustion engine usually comprises a ventilation device, which fluidically connects the crankcase to the air feed. Thus, the blow-by gases are conducted to the air feed, wherein the ventilation device can comprise an oil mist separator, which separates the blow-by gases from their oil component, thus returning the oil thus obtained back to an oil reservoir of the crankcase through a fluidic connection. As a rule, the air feed comprises a throttling device as well as a charging device, wherein the charging device serves for the power increase of the combustion engine, in particular upon a full load of the combustion engine. Practically, the ventilation device can also be divided into a full load feed and a part load feed, while the full load feed leads into the air feed upstream of the charging device and the part load feed leads into the air feed downstream of the throttling device. Since the gases returned to the air feed via the ventilation device are environmentally harmful, it is important to avoid escaping of these gases into the environment. In addition to this, such a leak results in ambient air being sucked in through the air feed and thus to a fault in the operation of the combustion engine.
To avoid and detect such a leak, a combustion chamber is known for example from DE 103 20 054 A1 which comprises air sensors within the ventilation device and the air feed.
The multi-component construction of the ventilation device, in particular the division into part load feed and full load feed however can additionally result in that a leak within the ventilation device cannot be avoided or detected. Thus, for example during the assembly of the ventilation device, a part of the ventilation device cannot be correctly installed or a leak within one of the feeds of the ventilation device is not detected, in particular by the sensor device.